New Polymers with Controlled Architecture

具有可控表面官能度的单分散树枝状大分子将通过两种方法制备。第一种方法涉及一种新的“收敛”方法，在这种方法中，大分子的生长从其外表面开始，并通过多官能团单体与正在生长的聚合物的单一反应基团的重复偶联向内进行，而第二种方法使用更经典的固相方法。“收敛生长”方法提供了对最终球形大分子外表面官能团的数量和空间位置的无与伦比的控制。一旦制备好，树枝状分子将被用来制备具有特殊结构和性质的新的大分子组装。这将通过在涉及接枝、嵌段聚合或偶联反应的过程中对表面官能团进行修饰来实现。特别是，将研究在树枝状大分子外表面形成受控位置的线性高分子链的生长。这些新的大分子组装体的合成将导致具有新性能的新材料，这些新材料由于它们不寻常的拓扑结构、它们均匀的小尺寸(30-100)A、它们的对称或不对称的表面官能化、强分子极的存在、手性的存在等而产生。这些新材料有望在各种领域中得到应用，如分子传输、催化和光电子学。

Monodispersed dendritic macromolecules having controlled surface functionality will be prepared by two methods. The first involves a novel "convergent" approach in which growth of the macromolecule starts at what will become its external surface and proceeds inwards through repeated coupling of a polyfunctional monomer to the single reactive group of the growing polymer, while the second method uses a more classical solid-phase approach. The "convergent growth" approach provides unparalleled control of both the number and the spatial location of the functional groups at the outer surface of the final spheroidal macromolecule. Once prepared, the dendritic molecules will be used to prepare new macromolecular assemblies with unusual architectures and properties. This will be done through modification of the surface functional groups in processes involving grafting, block polymerization, or coupling reactions. In particular, the growth of linear polymer chains form controlled locations on the outer surface of dendritic macromolecules will be studied. The synthesis of these new macromolecular assemblies will lead to new materials with novel properties resulting from their unusual topology, their uniform small size (30-100) A), their symmetrical or unsymmetrical surface functionalization, the existence of strong molecular dispoles, the presence of chirality, etc. Applications of these new materials are anticipated in areas as varied as molecular transport, catalysis, and optoelectronics.